\begin{tikzpicture}[scale=.8]
    \pgfmathsetmacro{\R}{1.5}
    \pgfmathsetmacro{\r}{1.2}

    \tkzDefPoints{0/0/O_1, 0/0/O_2} % O_1 = O_2
    \tkzDefPoint(15:\R){M}
    \tkzDefShiftPoint[O_2](60:\r){N}

    \tkzDrawCircle[thick](O_1,M)
    \tkzDrawCircle[thick](O_2,N)
    \tkzDrawSegments(O_1,M  O_2,N)
    \tkzLabelSegment[midway, below](O_1,M){$R$}
    \tkzLabelSegment[midway, left](O_2,N){$r$}
    \tkzLabelPoint[left](O_1){$O$}
\end{tikzpicture}

